#include "terminal.h"

#include <stdio.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <termios.h>
#include <unistd.h>

static struct termios original_termios;

void die(const char* message)
{
	/* Clear the screen */
	write(STDOUT_FILENO, "\x1b[2J", 4);
	write(STDOUT_FILENO, "\x1b[H", 3);

	perror(message);
	exit(1);
}

void disable_raw_mode()
{
	if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &original_termios) == -1)
		die("tcsetattr");
}

/* Disables any input and output processing from the terminal */
void enable_raw_mode()
{
	if (tcgetattr(STDIN_FILENO, &original_termios) == -1)
		die("tcgetattr");

	atexit(disable_raw_mode);

	struct termios raw = original_termios;
	raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
	raw.c_oflag &= ~(OPOST);
	raw.c_cflag |= (CS8);
	raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);

	raw.c_cc[VMIN] = 0;
	raw.c_cc[VTIME] = 1;

	if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw) == -1)
		die("tcsetattr");
}

int get_cursor_position(int* rows, int* cols)
{
	char buffer[32];
	unsigned int i = 0;

	if (write(STDOUT_FILENO, "\x1b[6n", 4) != 4)
		return -1;

	while (i < sizeof(buffer) - 1) {
		if (read(STDIN_FILENO, &buffer[i], 1) != 1) break;
		if (buffer[i] == 'R') break;
		i++;
	}
	buffer[i] = '\0';

	printf("\r\n&buffer[1]: '%s'\r\n", &buffer[1]);

	if (buffer[0] != '\x1b' || buffer[1] != '[') return -1;
	if (sscanf(&buffer[2], "%d;%d", rows, cols) != 2) return -1;

	return 0;
}

int get_window_size(int* rows, int* cols)
{
	struct winsize size;

	if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &size) == -1 || size.ws_col == 0) {
		if (write(STDOUT_FILENO, "\x1b[999C\x1b[999B", 12) != 12)
			return -1;
		return get_cursor_position(rows, cols);
	} else {
		*cols = size.ws_col;
		*rows = size.ws_row;
		return 0;
	}
}